This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Whowie (Australian Aboriginal)
The Whowie, a fearsome creature from Australian Aboriginal mythology, resembled a seven-metre long goanna with a huge frog-shaped head and six powerful legs. He lived in a cave on the banks of the Murray River that extended deep beneath the ground, and his trampling on the riverbanks outside his cave formed the sandhills of the Riverina district. Although slow, the Whowie was extremely stealthy and could kill and devour a whole tribe in a single meal.
The water rat tribe, having finally had enough of their suffering at the hands of the Whowie, instructed all the tribes in the area to gather together spears, stone axes, waddies, and many bundles of sticks. With the Whowie at the far end of his cave, they stacked the bundles in a great heap at the entrance and set them alight. After seven days the Whowie finally emerged, blinded and disorientated by the smoke, and the tribes succeeding in killing him with their weapons and freeing the land from a terrible menace.